Despite advances in public health and medical care, infectious diseases continue to cause considerable morbidity and mortality worldwide, and extract an enormous financial and societal toll even in developed countries due to factors such as emerging pathogens, AIDS or other immunocompromising conditions, and antimicrobial resistance. Between 1980 and 1992, the U.S. death rate from infectious diseases, excluding HIV/AIDS, actually rose by 22%. Although some progress has been made since, recent epidemiological data indicate that infections continue to account for one-fifth of deaths worldwide. Familiar bacterial pathogens such as Salmonella, Mycobacterium tuberculosis and methicillin-resistant Staphylococcus aureus contribute to the deaths of millions of people each year, while other pathogens such as Escherichia coli 0157:H7, Acinetobacter baumannii and Clostridium difficile have emerged as new threats. The specter of bioterrorism has heightened awareness that a better understanding of the pathogenesis of infection is needed. Of particular concern is the increasing prevalence of antibiotic-resistant bacteria at a time when the pipeline of new antimicrobial agents has run dry. The training of new scientists who can elucidate basic mechanisms of microbial pathogenesis will be critical for the formulation of improved strategies to prevent, diagnose and treat infectious diseases. This application for renewed support of a Training Program in Bacterial Pathogenesis centers around an established and highly interactive interdisciplinary research community and the University of Washington. The goal of the program is to provide comprehensive interdisciplinary training and mentorship for pre- and post-doctoral trainees who seek to understand fundamental cellular and molecular mechanisms of the interactions between bacterial pathogens and their hosts. This training will ultimately allo them to obtain new scientific insights as independent investigators that can lead to novel approaches for the prevention and management of infectious diseases.